System.Windows.Data Error: 4 : Cannot find source for binding with reference ...

When I run a DataGrid with Hierarchical data, I get the following binding exceptions in my output window.

System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='System.Windows.Controls.TreeViewItem', AncestorLevel='1''. BindingExpression:Path=IsSelected; DataItem=null; target element is 'ToggleButton' (Name=''); target property is 'NoTarget' (type 'Object')
System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='System.Windows.Controls.TreeViewItem', AncestorLevel='1''. BindingExpression:Path=IsSelected; DataItem=null; target element is 'ToggleButton' (Name=''); target property is 'NoTarget' (type 'Object')
System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='System.Windows.Controls.TreeViewItem', AncestorLevel='1''. BindingExpression:Path=IsSelected; DataItem=null; target element is 'ToggleButton' (Name=''); target property is 'NoTarget' (type 'Object')
System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='System.Windows.Controls.TreeViewItem', AncestorLevel='1''. BindingExpression:Path=IsSelected; DataItem=null; target element is 'ToggleButton' (Name=''); target property is 'NoTarget' (type 'Object')

Even though this is just a trace, I think it is slowing down the binding in the grid considerably. How can I fix this? Should I create a property "IsSelected" in my underlying data structure?

Here is a screenshot, in case that helps:

EDIT: This happens when the node does not have children, and therefore no ToggleButton !

Hello

Thanks for pointing this out! There was a bug in the Alloy theme causing this. This has been resolved which you can update through the next nightly build.

Jason Fauchelle

Solved. Thanks.

Also these.... Are they from your grid?

System.Windows.Data Error: 2 : Cannot find governing FrameworkElement or FrameworkContentElement for target element. BindingExpression:Path=ColumnDropRequestPosition; DataItem=null; target element is 'TranslateTransform' (HashCode=46965693); target property is 'X' (type 'Double')
System.Windows.Data Error: 2 : Cannot find governing FrameworkElement or FrameworkContentElement for target element. BindingExpression:Path=ColumnDropRequestPosition; DataItem=null; target element is 'TranslateTransform' (HashCode=29306526); target property is 'X' (type 'Double')

Yes these are also from the grid but they can be safely ignored.

Jason Fauchelle